Light Emitting Diodes (LEDs) are semiconductor devices that convert electricity into light using characteristics of compound semiconductors so as to enable transmission/reception of signals, or that are used as a light source.
Group III-V nitride semiconductors are in the spotlight as core materials of light emitting devices such as, for example, LEDs or Laser Diodes (LDs) due to physical and chemical characteristics thereof.
The LEDs do not include environmentally harmful materials such as mercury (Hg) that are used in conventional lighting appliances such as, for example, fluorescent lamps and incandescent bulbs, and thus are very eco-friendly, and have several advantages such as, for example, long lifespan and low power consumption. As such, conventional light sources are being rapidly replaced with LEDs.
Meanwhile, a conventional flip-chip type light emitting device may include a reflective layer which reflects light in order to allow light, emitted from an active layer, to escape from the light emitting device. At this time, the reflective layer formed of a reflective material such as silver (Ag) has low adhesive force with other layers, thus being easily peeled off, which may deteriorate the reliability of the light emitting device.